The version II has a much smaller lens hood.....and in the distance window...is missing the macro scale.....and also has a locking button to the right side to keep the lens from slipping during motion

also....when you zoom...the old version hood attached to the body and when the lens zoomed out, you never saw it do it....but on the new one...the hood attaches to the end of the filter ring...so as the lens zooms out...the hood goes out with it

I picked the lens up a few hours ago and it looks new as well it should considering the short time it's been out. I wasn't in the market for one but after seeing it on craigslist and what he was asking for it I could not pass it up. I was hoping to do some testing against my 24-105 to see how much sharper it is but with storm starting I will have to wait a few days. I took a few shots indoors with flash and it looks good.